Greenhouse Gases
Atmospheric concentrations of carbon dioxide, methane, and nitrous oxide – each tracked against pre-industrial baselines – alongside global temperature anomaly, Arctic sea ice extent, and ocean surface warming. Historical charts reveal the long-term rise of each gas and show how they translate into measurable change: land warming faster than sea, ice retreating, and a planet pressing against the limits set by the Paris Agreement.
Current Readings
Data: NOAA GML (CO₂, CH₄, N₂O — Mauna Loa & global network) · NOAA NCEI (temperature anomalies vs 1961–1990) · NSIDC (Arctic sea ice)
Monthly Indicators
CO₂, Temperature & Ocean Anomalies
Monthly · last 5 years · anomalies vs 1961-1990 baseline (NOAA NCEI)
CO₂ seasonal trend (NOAA GML, Mauna Loa) · temperature and ocean anomalies vs 1961–1990 baseline (NOAA NCEI)
Annual History
CO₂ & Global Temperature
CO₂ concentration (left axis) vs Land + Ocean temperature anomaly (right axis)
As CO₂ rises, global temperatures track upward in near-lockstep - a correlation that holds across every timescale. Sources: NOAA GML (CO₂) · NOAA NCEI (land + ocean temperature, vs 1961-1990).
All Greenhouse Gases – Percentage Rise
% above pre-industrial level – drag slider to zoom
All three gases as percentage increase above pre-industrial levels, showing how each amplifies the others' warming effect. Sources: NOAA Global Monitoring Laboratory via global-warming.org.
Global Warming – Land & Sea
Land-only temperature anomaly (left axis) vs sea surface temperature anomaly (right axis)
Land masses warm faster than oceans – confirming this is a whole-Earth system shift, not a local phenomenon. Sources: NOAA NCEI (land-only & sea surface temperature, vs 1961-1990).
Rising Carbon, Vanishing Ice
CO₂ concentration (left axis) vs global sea ice extent (right axis)
As CO₂ climbs, global sea ice drops – lost ice exposes dark ocean, absorbing more heat and accelerating warming further. Sources: NOAA GML (CO₂) · NSIDC via global-warming.org.
Greenhouse Gases
Atmospheric CO₂ Concentration
Yearly average CO₂ concentration (ppm) – drag slider to zoom
* 2026 is year-to-date (Jan-Aug only, partial year)
CO₂ is the primary driver of climate change, responsible for about two-thirds of total warming. Continuous measurements from Mauna Loa date back to 1958. Source: NOAA Global Monitoring Laboratory (Mauna Loa Observatory).
Atmospheric Methane Concentration
Yearly average methane concentration (ppb) – drag slider to zoom
Methane is over 80× more potent than CO₂ over 20 years. Major sources include agriculture, fossil fuel extraction, and wetlands. Source: NOAA GML via global-warming.org.
Atmospheric Nitrous Oxide Concentration
Yearly average N₂O concentration (ppb) – drag slider to zoom
N₂O has nearly 300× the warming potential of CO₂ over 100 years and also depletes the ozone layer. The primary source is agricultural fertiliser. Source: NOAA GML via global-warming.org.
Sea Ice & Ocean
Global Sea Ice Extent
Annual average sea ice extent (million km²)
Global sea ice (Arctic + Antarctic combined) reflects sunlight back into space. As it melts, darker ocean absorbs more heat, accelerating warming in a feedback loop. Source: NSIDC / NOAA via global-warming.org.
Ocean Surface Temperature Anomaly
Annual ocean surface temperature anomaly (°C)
* 2026 is year-to-date (Jan-Aug only, partial year)
Oceans absorb over 90% of excess heat trapped by greenhouse gases, driving coral bleaching, sea-level rise, and more intense storms. Anomalies relative to 1961-1990 baseline. Source: NOAA NCEI (global ocean surface temperature).
Explore
Explore Climate Data
FAQs
FAQs
What does the greenhouse gases page show?
Live atmospheric concentrations of the three main long-lived greenhouse gases - carbon dioxide (CO₂), methane (CH₄) and nitrous oxide (N₂O) - alongside their long-term ice-core records stretching back hundreds of thousands of years. Current values and recent monthly trends are in the live panels above.
Which greenhouse gases matter most for climate change?
Carbon dioxide is the largest single contributor to human-caused warming and the longest-lived in the atmosphere. Methane has a much shorter lifetime but a far stronger warming effect per molecule. Nitrous oxide has a long lifetime and is the third-largest contributor. Fluorinated gases (HFCs, PFCs, SF₆) and water-vapour feedback also play a role; the major three are tracked on this page.
Where does the greenhouse gas data come from?
Modern atmospheric measurements: NOAA Global Monitoring Laboratory, including the Mauna Loa Observatory and the global air-sampling network. Long-term ice-core records: EPICA, Vostok and Law Dome projects, archived at NOAA NCEI. Live monthly updates are sourced via the global-warming.org public API which mirrors the NOAA feeds.
How are the numbers expressed?
CO₂ is reported in parts per million (ppm). Methane and nitrous oxide are reported in parts per billion (ppb). Trend lines remove the seasonal cycle to show the underlying year-on-year change. Pre-industrial levels (around 1750) are noted on each chart for reference.
How often is this page updated?
Monthly atmospheric measurements refresh each month, typically within a few weeks of the measurement date. Ice-core records are static historical archives that do not change.
Is this page suitable for students studying climate change?
Yes. The greenhouse gases page covers material directly relevant to UK GCSE and A-level Geography (carbon cycle, climate change causes), IB Environmental Systems and Societies (Topic 3: Climate and energy) and AP Environmental Science (Unit 7: Atmospheric pollution, Unit 9: Global change). The long-term ice-core charts and live concentration data are particularly useful for illustrating the scale and pace of change since industrialisation. Citation formats for academic work are available on the Climate Education page.
What is the difference between CO₂ concentration and CO₂ emissions?
CO₂ concentration (measured in parts per million, ppm) is the amount of carbon dioxide currently in the atmosphere - it is what this page tracks. CO₂ emissions are the annual flow of new carbon dioxide released by human activity. Emissions are like water flowing into a bath; concentration is the level of water in the bath. Because CO₂ persists in the atmosphere for centuries, concentration continues to rise even as emission growth slows. Country-level emissions data is available on the CO₂ Emissions page.